Recovering the waste heat of smelters and kindred plants.



c. SfMMLER. RECOVERING THE WASTE HEAT OF SMELTERS AND KINDRED PLANTS.

APPLICATION FILED DEC-9.1913- 1,'151,831. A Patentd Aug. 31, 1915 iiwa w @FFIQE.

CABL SEMMLER. 0F WIESBADEZJ, GERMANY.

Zip, lication December 9, 1813.

invenion relates to a novel method or system of utilizing the waste heat inherent in the lay-products, etc., of smelters and kindred plants, such as the heat of blast furnaces and other gases.

W ith the methods hitherto known, the gases en'ianating from blast furnaces have been employed for driving gas engines, or boilers have been built into the exhaust gas passages. These methods however, did not fuliil their purpose because the various gases and other products generated in smelters and similar plants, yield their inherent heat but irregularly. ll ith an iron plant of considerable size, the available quantity of heat depends largely upon the operation of the blast furnaces. heat sources of diilcrent kind, for instance the gas supply to the engines, fails partially or totally, the Waste heat of the coke plant may be si'ibstituted. Thus With the present invention an economical recovery of the v/asteheat is rendered feasible because a plurality of heat sources of different kinds react upon a common heat absorbing medium such as distilled Water, for which purpose said. medium is made to traverse the different heat recovering appliances in series or in parallel. After this medium has thus absorbed the heat of all such appliances, it is conveyed to an accumulator in which Va porization takes place. I

As in this accumulator, the Waste heat of a. plurality of heat sources of difierent kinds, is collected, it does not matter if one of said sources fails temporarily, so that a substantially uniform heat su ply is stored in said accumulator, Which in. turn Warrants a constant operation of steam engine or other heat consuming appliance coupled to said urciinuiator. The heat absorbinp, medium heat carrier consists preferably of dis- Water to prevent the 'fori'nation of ans or rioa' it an that the i. such apparatus Specification of Letters Fates t.

lor heating or other purposes.

Ii -one (if the several i a. r" i arentea Aug. 3i, lulu.

Serial He. $35,531.

is efi'cetively prevented. in this Way, even relatively high temperatures may be profit:

ably utilised because toe heat transfer eii'eets a thorough cooling: of the several hot media. The pressure of the heat carrier is finally relieved within the :m'umulator, to here cause a lively generation of steam which may be employed for driving an engine and The heat carrier which describes a rycle may also beutilized to heat a heat absorbing medium of a second cycle such as cold vapor fluids for driving turbines, etc.

My-novel method has-the important advantage that temperatures which vary \vithin a wide range may be utilized. Thus the high temperaturml heat sources may collectively influence a first cycle of a heat carrier While the heat sources oi" lower teuu'ierature may be united to in liuence one or more other cycles, which cycles may include separate. heat accunmlators. Owing to this graduation of the. b .llt sources with respect to their temperature a most economical operation oitlre heat reeoverv system is attained, because tlifliezlt car ier my be preheated in. a cycle of low temperatured apparatus to be subsequently subjected to the action of a cycleof higher temperatured apparatus, etc.

In order to prevent the heat carrier in lieu of passing through the zuccumulator, from circulating between two heat yielding apparatus which should have like temperatures but have in fact different temperatures, the several branches of the heat carrier are provided with. pressure regulating means, so that this carrier must invariably circulate through the accumulator. It is also necessary to provide a check Valve for the heat The letter a. indicates the heat accumulator communicating near its bottom with a pump Z adapted to force the liquid heat carrier into conduit 0. The latter communicates in turn with a plurality of heat transferring apparatus a 6Z2, (Z which may be respecl L by the waste of a Cowper a paratus, flue gases, a forge, and the coke quenching ater. These apparatus are through branches 6 ctintrolied by yalves 6,

connected to a return conduit 7 controlled by check valve After the heated carrier has passed through valve g, its pressure is relieved so that a lively generation of steam will take place Within accumulator a. This steam is conveyed through pipe h to an engine or other steam consuming apparatus 1', While the condensate gathering in condenser is is by pump 6 conveyed into conduit 0, so that in this Way a complete cycle of the heat carrying medium is established.

With the construction shown in Fig. 2, accumulator 4; contains a vaporizer m which is heated by the heat carrier passing through the accumulator. Vaporizer on, contains preferably a cold vapor fluid which is con- ,veyedthrough pipe a to a cold vapor engine a, thefcondeusate collecting in condenser 7? being, by pump K and pipe a returned to thevaporizer. With this device the check valve 5/ may be omitted in case the temperature is below 100 cent-igrade.

Fig. 3 illustrates a plant in which the heat recovery is effected stepwise, by sending the heat carrier through heat transfer apparatus (Z, (Z and then through apparatus (F, d to be further heated. In some cases the parts (l and (5, may for instance be arranged Withi a Cowper apparatus 0*, While the parts (1, al are installed within a heating flue a. The apparatus (Z, al are .jointly connected to a first accumulator a, and the apparatus of, d are jointly connected to a. second accumulator a (Fig.4), Whereby the arrangen'ient is such, that apparatus (Z is subjected to a higher tempen ature than apparatus (2 owing-to the flow of In this way, accumulator a re-' ceives a temperature that is higher than that 40 of accumulator (61. It is thus obvious that the heat transfer apparatus and the accumulators may be combined in such a manner that even small quantities of heat may be completely recovered in an economical manner, Without in any way impairing the uniformity and safety of the heat recovery system.

I claim:

System of recovering waste heat, comprising a heat-accumulator adapted to contain a liquid heat-absorbing medium, a plurality of heat-yielding devices that are adapted to receive their heat from independent sources of different kinds, 9; first conduit connecting the lower portion of the accumulator with all of said heat-yielding devices, a pump forming part of said first conduit and adapted to convey the liquid heat-absorbing medium from the accumulator to the heat yielding devices, a second conduitconnecting all of said heat-yielding devices with the upper portion of said heataccumulator, and a check valve forming part of said second conduit and located in prox-- imity to the accumulator, said check valve preventing vaporization of the heated medium during its passage through the second conduit. I

CARL SEMEI 311E118.

WVitnesses 

